From 41a4695ca46d8798f89b477855973eb2ad3f4f69 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 27 Feb 2013 08:37:56 -0800 Subject: [PATCH] Yama: do not modify global sysctl table entry When the sysctl table is constified, we won't be able to directly modify it. Instead, use a table copy that carries any needed changes. Suggested-by: PaX Team Signed-off-by: Kees Cook --- security/yama/yama_lsm.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c index 13c88fbcf037..24aae2ae2b30 100644 --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -379,20 +379,17 @@ static struct security_operations yama_ops = { static int yama_dointvec_minmax(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { - int rc; + struct ctl_table table_copy; if (write && !capable(CAP_SYS_PTRACE)) return -EPERM; - rc = proc_dointvec_minmax(table, write, buffer, lenp, ppos); - if (rc) - return rc; - /* Lock the max value if it ever gets set. */ - if (write && *(int *)table->data == *(int *)table->extra2) - table->extra1 = table->extra2; + table_copy = *table; + if (*(int *)table_copy.data == *(int *)table_copy.extra2) + table_copy.extra1 = table_copy.extra2; - return rc; + return proc_dointvec_minmax(&table_copy, write, buffer, lenp, ppos); } static int zero;